To inform the level of attention to be given by antiretroviral therapy (ART) programs to HIV drug resistance (HIVDR), the authors used an individual-level model to estimate its impact on future AIDS deaths, HIV incidence, and ART program costs in sub–Saharan Africa (SSA) for a range of program situations. They applied this to SSA through the Spectrum-Goals model. In a situation in which current levels of pre-treatment HIVDR are over 10% (mean, 15%), 16% of AIDS deaths (890 000 deaths), 9% of new infections (450 000), and 8% (US$ 6.5 billion) of ART program costs in SSA in 2016–2030 will be attributable to HIVDR.